The hiller furrower attachment makes the furrows. You determine how wide the hills are by the distance to the next furrow. You have to till the entire area first then come back with the attachment and make the furrows.

OK. I'm gonna show my ignorance here....
So, what you're saying is the hills are actually at normal ground level? So, you basically till your whole garden, then come back and cut ditches (furrows?) at some distance apart, which establishes the width of the hills? What happens to the material that's removed to create the ditch (furrow).

I was of the impression that I would till my garden, then go back over it with the hiller attachment (only), leave one wing off, then the tiller would kind of throw soil up in a mound beside the tiller. Then I would make a pass in the opposite direction, some distance away and the tiller would throw soil towards the other side of the hill establishing the overall width of the hill?

What am I misssing?

The dirt from the furrows you cut is pushed to the sides of the tiller and becomes part of the hills. The hills are at ground level but are a little higher because of the dirt from the furrow. If you make the hills wide, you will need to even the dirt thrown on the hill by the furrower for a nice raised bed look. They make a raised bed attachment for the BCS tillers that have two blades that are adjustable. I'll leave a link to that picture.

Here is a link that might be useful: Bedshaper

OK. I couldn't find the bedshaper on the link you provided but those bcs 2 wheel tractors are intersting.

Anyway, I think I understand now.

I have a trusty old Horse model I gardened with for years using the hiller/furrower attachment. 30 inches would be about just right. I never tried it with just one wing. I think that might make it a little awkward/unbalanced for moving ahead but maybe not. I highly recommend Gardenways old gardening book that came with the Troy Bilts of yore.. The Joy of Gardening by Dick Raymond. Excellent book geared towards using your Troy Bilt and wide bed planting

pkguy-
Well, I just purchased the pony.... so am I not going to be able to get the 30" wide hills?

Thanks for the info on the book. I'm going to see if I can locate one.

I have used the Hiller/Furrower on both my Horse and Pony If you set the wings out all the way, it should do a good job for you. Althou it does better on the Horse because of weight and HP.